This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Melissa Harrington Investigating the Neurobiology of Sensory Processing the Learning in and Invertebrate Model System Our program has two main objectives: 1) the use of multi-electrode physiology to characterize the network architecture and neurophysiology of snail brains engaged in sensory processing;and 2) the use of targeted gene knock-out in live, adult snails to elucidate the molecular physiology of sensory processing and learning. The current work and research funding of one PI (Harrington) is focused on using a 64-electrode microarray to record electrical activity from the cerebral ganglia of snails and observe changes in that activity caused by sensory input and processing. Dr. Harrington and Dr. Pokrajac are collaborating on developing computational analysis tools and models for the multi-electrode data that Dr. Harrington and her students are collecting. The third PI (Davis) is planning to utilize the behavioral model of slime trail following in the predatory snail, Euglandina rosea, (the wolfsnail) to evaluate molecular mechanisms underlying sensory processing and learning. Wolfsnails naturally follow, and can distinguish between, slime trails left by prey snails from trails left by their own species and rapidly learn to follow artificial trails of novel compounds associated with food rewards. This part of the project involves cloning selected genes related to signal transduction from the snails and using the sequence to generate interfering RNAs for RNA interference (RNAi). The goal of the project is to use targeted, transient gene knock-out with RNAi to investigate the role of particular neurotransmitter systems involved in slime trail recognition and learning.